CVE-2026-119552
Uptime Kuma through 2.5.8 Race Condition Admin Creation via Setup Handler
- State
- Published
- Severity
- 6.3 Medium
- Published
- Oct 30, 2026
- Updated
- Oct 30, 2026
- Reserved
- Oct 30, 2026
Description
Uptime Kuma through 2.5.8 contains a race condition in the Socket.IO first-run setup handler that allows unauthenticated attackers to create an additional administrator account. Attackers can send concurrent setup requests during the bcrypt hashing window to bypass the empty user table check, then modify monitors, API keys, and enable disableAuth.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 6.3 Medium | CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N | VulnCheck |
| 3.1 | 4.8 Medium | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N | VulnCheck |
Weaknesses
- CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition
Affected Products
| Product | Versions |
|---|---|
uptime-kumalouislam |
|
References
- https://github.com/louislam/uptime-kuma/blob/2.5.8/server/server.js#L705-L722technical-description
- https://abraxaslabs.tech/research/uptime-kuma-setup-toctouthird-party-advisory
- https://github.com/louislam/uptime-kumaproduct
- VulnCheck Advisory: Uptime Kuma through 2.5.8 Race Condition Admin Creation via Setup Handlerthird-party-advisory
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